Process of treating materials.



a citizen of the United 'rENtr OFFICE FREDERICK W. -YOST, OF CHICAGO,ILLINOIS.

PROCESS OF TREATING MATERIALS;

Specification of Letters Patent.

Patented Sept. 19, 191 1. Renewed January 16, 1911. Serial No.

To cilZ' whom it 1; my concern Be it known that I, FnnnnmoK \V. Yos'r,States, residing at Chicago, in the county of Cook and State oflllihois, have indented certain newand useful .llnpr'oven'ients inProcesses of Trenting ilatcrials,'ofwhich the following-is aspecification.

My invention relates to the treatment of materials; and it comprises aprocess wherein a reaction initiated in one region of a mass of materialis ca'iu-ied topropagate through the mass by proper control 0 bonditionsand by the aid of a IQfltilOIl-SHP- porting gas conducted throughthe'interior of the mass in a direction other than the course ofreaction; am it also comprises more particularly, but not exclusively,the treatment of finely divided material in a stationary or movable massby roasting, eiilcining or reducing and agglomernting one or more ofthecontained elements, all as set; forth and as more fully hereiuitt'tcrclaimed. 7 y

One of the chief objects attained by my invention is the high efliciencyof the proce s, because the gaseous elen'ient. iggbronght to the zone ofreaction uncontaminated by.

the products of reaction, since the reaction producing gas 15 conductedthrough the material in a direction other than the course V of reaction.And of reaction untreated ceptible of full control, because theuntreated material is acted upon only by the energy developed at thezone of reaction. nother important object attained is the since thewaste products are not conducted through the lengthened life of anyapparatus. employed,

because in my process the volatile products escape from the interior ofthe mass at the same surface at which the reaction is initiuted,therefore, the destructive agencies areall confined to one region of theapparatus and that part of the apparatus may be formed of materiallargely uninfiuenced by such agencies.

A further attainment is the economical and rapid treatment of thematerial caused by the intimate contact between the particles of themass and thereaction-supporting gas.

y process can be carried on intermittently in the vvell known forms ofpot roastmg apparatus or in any reverberatory roastmg furnace providedwith a perforated material the reaction is sus-,

forms of the process lime easting, pot roasting,

the finely divided hearth, or continuohsly in well known forms of chaingrate stoker furnaces, where the material can be treated 'in h masshaving definite bounding surfaces.

\ My process may be advantageously u ,d for roasting sulfid ores andI'elntd mai tcrials, Where, as is usual in'the ait, sulfids are to beoxidized to form either a granular or an agglomerated body of oxids. Ithas been the practice heretofore to roast many of these ores in someform of reverberatory furnace, where heating and roasting of the chargeare chiefly brought iabout by agitation of the ore mass thus orming andexposing new surfaces to the hot furnace gases, but it is impossible bythis method to heat and oxidize uniformly all the particles of thecharge. Recent improvements pro ride for the passage of air or othergases through the ore mass, but the heating of the chnrge neverthelesslacks uniformity, because the heating still depends upon the continualformation of. new surfaces by rabbling. The various developments of theheap roasting process are alsolargely used for roasting sulfid ores. Inthe earlier a large mass of ore is ignited at the bottom and naturaldraft,

which is subject to slight control,pr agates combustion toward the top,the pro nets of combustion from one region passing through adjacentregions and materially interfering with the combustion in those regions,with the result that some portions of the heap are over-burned andclinkered and other portions are under-burned ,andfret'ain much sulfur.In the later developmentsv of the heap roasting process, variouslycalled and blast roasting, a controlled air blast is introduced at theignited surface of the charge, whereby combustion is propagated in thedirection of the blast through the interior of the ore mass, andsintermg, which is the chief function, is almost simultaneous withcombustion, therefore, there is no separate control of the roastreaction.

In my process when ioo applied to sulfid ores ore is charged into anysuitable apparatus, and air, introduced at the lower surface of thecharge, is conducted upward throughthe interior of the mass, theopposite surface of the charge is ignited and the heat, followed by theoxidation of sulfide, is propagated by internal combustill tiondownward, the plane of ignition passing downward through the charge fromthe upper tothc lower surface, or passing backward against the flow ofthe air, 'while'the volatile products of combustion escape at the uppersurfacelwithout interfering with the reactions in the zone ofcombustion. The regulation and exact control of chemical thermal andother conditions in the zone of combustion therefore simple andracticable. If there is sufficient sulfur in t e material forself-supporting combustion, after ignition, the process canbe carried onin an open top receptacle; if there is not sufficient sulfur to supportcontinuous combustion the process can be carried on in a reverberatoryfuxnace with a perforated hearth, or in a suitable form of chain ratestoker furnace,

where a moving bodyo hot gases generated by the combustion of extraneousfuel, can be maintained in contact with the upper surface of the charge.l'V here the material is deficient in sulfur it may be necessary, and isfrequently advanta cons to add combustible elements to the merge so thatthe heat may be propagated more efficiently through the mass. It may. bedesirable to moisten the charge so as to form interstices for theuniform distribution of the air through the mass. The temperature in thezone of reaction may be regulated, or the character of the reaction maybe varied, by

the addition of steam .or other modifying element to theair conductedthrough the interior of the mass.

An agglomerated productmay be made, provided the elimination of sulfurto the lowest attainable degreeis not requircd,by adding a suitablecombustible element to the material of the charge or "to the airconducted through the interior of the mass, or by heating the airconducted through the interior of the mass, or by various other meanswhich will properl intensify the reaction in the zone of com'Jlll-ltlOll. Whether the final product is to he granular oragglomerated, the conditions relating to the composition of the charge,this composition and temperature of the igniting or heating gases, thecomposition, icn'lpcralurc and pressure of the combustion-soppm-tinggas, elm, nulstbent-openly correlated, to produne the particular resultdisirod, audoach of these conditions must bo properly con trolled topropagate the desired reaction ll:l'ol|,' {'-ll the charge in thedesired nnlnncr. My process also may be used for burning or calcininglimestone, lmuxile..or similar material, \\'ll(lt the chic! object isthe olitui ualioi'i of combined water and the deco1nposition ol'carlmnalos. 'Such material, when in lump l'oruuis counnouly calcined ina u -rlical slack where the fuel is burned either iuroutact with thecharge or in a zaau'atr. l'urnacc, but. in either case the calcininggases, when they reach the zone of reaction, are largely vitiated byproducts of combustion. Such material, in smaller form, is sometimescalcined in a rotary -kiln where there is a large waste of fuel, becausethe hot gases act usefully only upon the small amount of material lyingon the bottom of the kiln the entire up er part of which forms anunobstructed ue permitting the gases to pass without hindrance to thestack.

In my process when applied to limestone or similar material, the finelydivided material is intimate] mixed with combustible elements and IScharged into a reverberatory furnace provided with a perforated hearthor into a suitable form of chain grate Stoker furnace. Air, int-roduccdat the lower surface of the charge, is conducted upward through theinterior of the mass; the oposite surface of the charge is heated bycontact with the hot furnace gas-eta, generated by the combustion ofextraneous fuel, and the heat, followed by the elimination of combinedwater and the decomposition of carbonates, is ropagated by internalreaction downward tiirough the charge from the upper to the lowersurface while the volatile products escape atthe upper surface and jointhe furnace gases. The intermixed fu'l in any region is consumed by theinte nal reaction only when the hot combustion zone, in its downwardprogress, reaches that region and the small. particles of fuel releasetheir heat only at -.thc time and at the place when and where 'it isneeded. In this case also, it ma be desirable to moisten the charge toma to it more porous, and likewise, modi'l'yin clel'flOlliS may be addedto the air con noted through the interior of the mass to control eitherof those. results can be obtained by' lnodiliiallious outlined 'above.

My process is well adapted for the produoliou of sponge iron by reducingand ugi gloiucraling iron oxidorcs or related metal. bearing material.'lluufinoly dividcd'ore is intiulatel'y mixed with combustible elemoldsand is charged into a rovorberatory furnace provided with a perforatedhearth or into a suitable form of chain grate stoker furnace. Acombustible gas, such as ating reaction and this interior of thecombustible gas.

blast furnace gas or reducer gas, introduccd at the lower sur ace of thecharge, is conducted upward through the interior of the mass, theopposite surface of the charge bo y is heated by contact with the movinof hot furnace gases and the heat, to lowed by the reduction of oxidsand the agglomeratioii of ore particles, is ropagated by internalreaction downwar through the charge from the u per to the lower surfaceWhile the volati e' products and gases formed from the components of thecharge escape at the upper surface, Where their complete combustion addsto the temperature and volume of the furnace gases. An essential part ofthis treatment is the maintenance of highly reducing conditions in theinterior of I may be secured by the use of smaller proportions of theheat-developing components in the charge with larger volumes ofcombustible gas conducted through the mass or with larger proportions ofthe heat developing components in the charge with smaller volumes 'ofcombustible gas conducted through the mass. The degree of reduction maybe controlled by the addition of steam, or other modifying element, tothe combustible gas conducted through the mass. When the chief object isthe making of an agglomerated product, and when it is desired to reducethe oxids only to such a degree as may be required to initiate theagglomcrating reaction, hot or cold air may he conducted through theinterior of the mass instead of In this case an important feature of thetreatment is to maintain in the interior of the charge the leastdegreeof reduction that will initiate the agglomercondition may be secured bythe use of cold air together with a reduingiurnace flame and a minimumof carbonaceons material in the .charge or by the use of hot. airtogether with an oxidizing furnace flame and a minimum of carbonaceousmaterial in the char 0. 'Thc reaction may -he further controlled by" theaddition to the a modifying element.

I do notjwish to be limited to treatm'ent ofthe specific materialsdescrjbed in the examples set forth, nor do I wish to be limited to thespecific details of treatment there described, nor merely to thespecific process described, since it will be evident to those skilled inthe art that this invention plies to the treatment of an material, orany mixture of materials, fo such a nature that a reaction started inone region of a mass can. be propagated through the whole mass ir ofsteam or other by proper control of chemical, thermal and the mass;these conditions having definite bounding lllOll-SUPPOI'ling ing orreducing and agglomcrating, but may include any treatment which produceseither an endothermic or exothermic reaction. It

also will be evident that the gaseous element can vary widely as tocomposition, and

tenor of the mass in a direction other than the course of the gaseouselement.

In all of the examples set forth I have described a downward propagationof the reaction and an upward course for the reaction-supporting gas butfor dill'crcnt condltions I may prefer to propagatet'tj'e I'Sitlfl tionupward, or in anyot'hcr dircctioh, pro vided the gaseous. elementconducted in a direction other than tlucourse of reaction. I also havedescribed, in thc tPXtlllljJltS set forth, conditions which result inthe forum tion of volatile products of HEtHllUll, but it will beevident: that non-volatile ,u'odurts of reaction will be formcd when thereaction is of such a character that the gaseous element conductedthrough the interior of the mass is absorbed by material of the charge;-

It is to be understood that the words, finely divided, as herein used,have ref-. ercnce to any degree of subdivision that best: adapts thematerial to treatment by my PIOCGSSfllS some materials respond totreatment better when in a relative] y coarse condition while othermaterials respond totteat ment only when in a finely divided state. Itis to be also understood, that where the material is described in theclaims as containing various components, the various components may beoriginally contained in the material, or they may be added to thematerial to prepare it for treatment.

What I claim is:

1.The process of treating finely divided material containing heatdeveloping components, which comprises initiating a reaction at onesurface of a. mass of material having definite bounding surfaces andcapable of undergoing a propagative reaction, said mass being ofsubstantially uniform character throughout, introducing a rear- -gas atanother surface of the mass, conducting the rcaction-supportiug gasthrough the interstices of the mass, and controlling conditions so as tocause an in ternal propagation of-the-reaction throngh but the body ofsuch mass, substantially as described.

2. The process of treating finely divided material containing heatdeveloping components, which comprises initiating a reaction at onesurface of a mass of material surfaces and ca- 'pable of undergoing apropagative reaction, said mass being of substantially uniform characterthroughout, introducing a reaction-supporting gas at another surface ofthe mass, conducting the reaction supporting gas through the intersticesof the mass, controlling conditions so as to cause an internalpropagation of the reaction throughout the body of such mass, andwithdrawing the volatile products of reaction at the surface of initialreaction, substantially as described.

3. The process of treating finely divided material containing heatdeveloping components, which comprises initiating a reaction atonesurface of a mass of material having definite bounding surfaces and.capable of undergoing a propagative reactioii, said mass being ofsubstantially uniform character throughout, introducing areaction-supporting gas at the opposite surface of the mass, conductingthe reaction-supporting gas through the interstices of the mass,controlling conditions so as to cause an internal pro negation of thereaction throughout the body of such mass, and withdrawing the volatileproducts of reaction at the surface of initial reaction, substantiallyas described.

i. The process of treatiu r finely divided material containing gasfbrming components, which comprises initiating a reaction atone surfaceof a mass of material having definite bounding surfaces and'capable ofundergoing a propagative reaction, said mass being of substantiallyuniform character throughout, introducing porting gas at another surfaceof the mass, conducting the reaction-supporting gas through theinterstices of the mass, and controlling conditions so as to cause aninternal propagation of the reaction throughout the body of such mass,substantially as described.

5. The process of treating finely divided material containing gas nents,which comprises initiating a reaction at one surface of a mass ofmaterial having definite bounding surfaces and capable of undergoing apro]'n1gali\-e reaction, said mass being of substantially uniformcharacter throughout, introducing a reactionsupporling gas at anothersurface of the mass. conducting the reaction-supp'ortiug gas through theinterstices o the mass, controlling conditions so as to cause aninternal propagation of the reaction throughout the body of such mass,and withdrawing the. volatile products of reaction at the surface o Iinitial rmction, substantially as described.

6. The process of treating finely divided material containing gasfori'ning conip'oncnts, which comprises initiating a reaction at onesurface of a. mass of material having definite bounding surfaces andcapable of undergoing a propagati vc reactiomsaid mass being ofsubstantially uniform character throughout, introducing arcactibn-supporta reaction-sup-- forming compoing gas at the oppositesurface of the mass, conducting the reaction-supporting gas through theinterstices of the mass, controlling conditions so as to cause an.internal propagation of the reaction throughout the body. of such mass,and withdrawing the volatile products of reaction at the surface ofinitial reaction, substantially as described.

7. The process of treatin finely divided material containing heatceveloping components, which comprises heating one surface of a mass ofmaterial having definite bounding surfaces and capable of undergoing apropagative reaction, said mass being of substantially uniform characterthroughout, introducing a. reaction-producing gas at another surface ofthe mass, conducting the reaction-producing gas through the in tersticesof the mass, and controlling conditions so as to propagate the heatthroughout the body of such mass by an internal reaction, substantiallyas described.

8. The process of treatin finely divided material containing heatdeveloping components, which comprises heating one surface of a mass ofmaterial having definite bounding surfaces and capable of undergoing apropagative reaction, said mass being of substantially uniformcharactcrthroughout, introducing a reaction-producing gas at anothersurface of the mass, conducting the reaction-producing gas through theinterstices of the mass, controlling conditions so as to propagate tieheat throughout the body of such mass by an internal reaction, andwithdrawing the volatile products of reaction at the surface of initialheat, subgstautially as described.

9. The process of treating finely divided. material containing heatdeveloping components, which comprises heating one surface of a mass ofmaterial having definite bounding surfaces and capable of undergoing apropagative reaction, said mass being ofsubstantially uniform characterthroughout, introducing a reaction-producing gas at the opposite surfaceof the mass, conductingfithe reaction producing gas through the iueistiws of the mass, wntrolliug conditions so as to propagate the heatthroughout the body of such mass by an internal reaction, andwithdrawing the volatile products of reaction at the surface of initialheat, substantially as described.

10. The process of treating finely divided material containing heatdeveloping components, which comprises heating the upper surface of amass of material having definite ing a propagativereaction, said massbeing of substantially uniform character througlr out, introducing areaction-producing pm at the lower surface of the mass, conducting thereaction-producing gas upward through the interstices of the mass,eimtrolling conbounding surfaces and capable of under-gm ditions so asto propagate the heat downward throughout the body of such mass by aninternal reaction, and withdrawing the volatile products of reaction atthe surface of initial heat, substantially as described.

11. The process of treating finely divided material containing gasforming components, which comprises heating one surface of a mass ofmaterial having definite bounding surfaces and capable of undergoing apropagative reaction, said mass being of substantially uniform characterthroughout, introducing a reaction-producing gas at another surface ofthe mass, conducting the reaction-producii'ig gas through theinterstices of the mass, and controlling conditions so as to propagatethe heat throughout the body of such mass by an internal reaction.substantially as described. 12. The process of treating finely dividedmaterial containing gas forming componcnts, which comprises heating onesurface of a mass of material having definite bounding surfaces andcapable of undergoing a propagative reaction, said mass being ofsubstantially uniform character throughout, introducing areacLion-producing gas at another surface of the mass, coiiiducting thereaction-producing gas through the interstices of the mass, controllingconheat.

ditions so as to propa ate the throughout the body of sue mass by aninternal reaction, and withdrawing -t ie volatile products of reactionat the surface of initial heat, substantially as described.

13. The process of treating fiinel'y divided material containing gasforn'iing components, which comprises heating onesurface of a mass ofmaterial having definite bounding surfaces and capable of undergoing apropagative reaction, said mass being of substantially uniformcharacterthroughout, introducing a reaction-prmlucing gas at the opposite surfaceof the mass. conducting the reactionreducing gasthrough the intersticesof t e mass, controlling conditions so as to propagate the heatthroughout the body of such mass by an internal reaction, andwithdrawing the volatile products of reaction at the surface of initialheat, substantially as described.

14. The process of treating finely divided material containing gasforming components, which comprises heating the upper surface of amassof material havng definite bounding surfaces and capable of ni'ulergoinga propagative reaction, said mass being of substantially uniformcharacter throughout. introducing a reactionprmlucing gas at the lowersurface of the mass, conducting the reactionu'oducin r was u )ward throu'h the interstices of the mass, controlling conditions so as topropagate the heat downward throughout the body of such mass by aninternal reaction, and withdrawing t-he volatile pioducts of reaction atthe surface of mitia heat, substantially as described.

15. The process of treatln finely divided n 1aterial containingcombustible components which comprises heating one surface of a mass ofmaterial having definite bounding surfaces and capable of undergoing apropagative reaction, said mass being of substantially uniform characterthroughout, in-

troducing a combustion-supportmg gas at another surface of the mass,conducting the conibustion-supporting gas through the interstices of themass, and controlling conditions so as to propagate the heat througlbout the body of such mass by internal combustion, substantially asdescribed.

16. The process of treatin finely divided material containing combustile components, which comprises heating one surface of a n'iass ofmaterial having definite bounding surfaces and capable/of undergoing apropagative reaction, said mass being of substan tially uniforu'lcharacter throughout, intro ducing a combustionsupporting gas at anothersurface of the mass, conducting the andwithdrawing the volatile productsof 5 col'nbustion at the surface of initial heat, substantially asdescr1bed.

17. The process of treating finely divided material containingcombustible components,

which (JOIIIIH'l-SOS heating one surface of a mass of material havingdefinite bounding surfaces and capable of undergoing a propagativoreaction, said mass being of substantially uniform character throughout,intro ducing a, co!Iibustion-supporting gas at the opposite surface ofthe mass, conducting the combustion-s1ipporting gas through theinterstices of the mass, controlling conditions so as to propagate theheat. throughout the body of such mass by internal combustion,

and withdrawing the volatile products of combustion at the surface ofinitial heat, substantially as described.

18. The process of treating finely divided material containingcombustible components, 1 15 which comprises heating the upper surfaceof a mass of material having definite bounding surfaces and capable ofundergoing a propagative reaction, said mass being of substantiallyuniform character throughout, in-

troducing a combustioirsupporting gas at the lower sl'lrface of themass, conducting the combustionsupporting gas upward through theinterstices of the mass, controlling conditions so as to propagate thebeat downward throughout the body of such mass by internal combustion,and withdrawing the volatile products of combustion at; the uppersurface, substantially as described. 1

19. The process of treating linely divided 1 0 material containingheatdeveloping components, which com rises transmitting heat from a movingbony of hot gases to one surface of a mass of material capable ofundergoing a propagative reaction, introducing a reaction-producin gasat another surface of the mass, conducting the reactionproducing gasthrough the interstices of the mass, and controlling thermal and otherconditions so as to ropagate the heat throughout the body 0? such massby an internal react-ion, substantially as described.

20. The proccss'of treating finely divided material containing heatdeveloping componentsywhich comprises transmitting heat from a movingbody of hot ases to'one surface of a mass of materia capable ofundergoing a propagative reaction, introducing a reaction-producing gasat the opposite surface of the mass, conducting the reaction'producinggas through the interstices of the mass, controlling thermal and otherconditions so as to propa ate the heat throughout the body of such massby an internal reaction, and withdrawing the volatile products of:reaction at the surface of initial heat, substantially as described.

21. The process of'treating finely divided material containing heatdeveloping com- ,mnents, which comprises transmitting heat from a movingbody of hot gases to the 11 )per surface of a mass of material capable oundergoing a propagative reaction, introducing a reaction-producing gasatthe lowerssurface of the mass, conducting the react-1on producing gasupward through the interstices of the mass, controlling thermal andother conditions so as to propagate the heat downward throughout thebody of such mass by an internal reaction, and Withdrawing the volatileproducts of reaction at the upper surface, substantially as described.

22. The process of treating finely divided material containing gasforming components, which coln 'n'ises transmitting heat from a movingbody of hot gases to one surface of a mass of material capable ofundergoing a propagative reaction, introducing a reaction-producing vgasat another surface of the mass, conducting the reactionproducing gasthrough the interstices of the mass, and controlling thermal and otherconditions so as to propagate the heat throughout the body of such massby an internal reaction, substantially as described,

23. The process of treating finely divided material containing gasforming components, which comprises tr nsmitting heat from a moving body.of h t gases to one surface of a mass of.;material capable ofundergoing a propagative react-ion, introducing a reaction-producing gasat the opposite surface of the mass, conducting the re action-producinggas through the interstices of the mass, controlling thermal and otherconditions so as to propagate the heat throughout the bod of such massby an internal reaction, an Withdrawing the volatile products ofreaction at the surface of initial heat, substantially as described.

24. The process of treating finely divided material containing gasforming components, which comprises transn'iitting heat from a movingbody of hot gases to the upper surface of a mass of material capable ofundergoing a propagative reaction, introducing a reaction-producing gasat the lower surface of the mass, conducting the reactionproducing gasupward through the interstices of the mass, controlling thermal. andother conditions so as to propagate the heat downward throughout thebody of such mass by an internal reaction, and withdrawing the volatileproducts of reaction at the upper surface, substantially as described.

25. The process of treating finely divided material containingcombustible components, which comprises transmitting heat from a movingbody of hot. gases to one surface of a mass of material. capable ofundergoing a propagutive reaction, introducing acon'ibpsli'on-siipporting gas at another surface oi the mass, comluctingthe comlmstion-supporting gas through the interstices of the mass, andcontrolling thermal and other conditions so as to propagate the heatthroughout the body of such mass by internal combustion. substantiallyas described.

26. The process of treating finely divided material containingcomlmstible components, which comprises transmitting-heal from a movingbody of hot gases to one surface of a mass of material capable ofundergoing a propugativc reaction, introducing a romlmstiou-supportinggas at the opposite surface of the mass, conducting the comlntstion-slIpporting gas through the interstices of the mass, controllingthermal and other conditions so as to propagate the heat throughout thebody of such mass by internal combustion, and Withdrawing the .\"olatilcproducts of combustion at the sur' face of initial heat, substantiallyas described. a

27. The process of treating finely divided malorial containingcombustible components, which comprises transmitting heat from a movingbody of hot gases to the upper surface of a mass of material capable ofundergoing a propagative reaction, introducing a con'ibustion-supportinggas at the lower surface of the mass, conducting thecombustion-supporting gas upward through the interstices of the mass,controh ling thermal and other conditions so as to propagate the heatdownward throughout the body of such mass by internal combusthroughoutthe body of such from a moving agative lion. and withdrawing thevolatile products of combustion at the upper surface, substantially asdescribed.

28. The process of treating finely divided material containingcombustible and other components. which comprises transmitting heat froma moving body of hot upperkurl'aee ot' a mass of material. capable ofundergoing a propagative reaction, introducing a gas reactive with someof the components of the niatcrialat the lower surl'ace' of the mass,conducting the reactive gas upward through the interstices of the mass,controlling thermal and otherconditions so as to propagate the heatddivnward ternal combustion, and withdrawing the volatile products ofcombustion at the upper surface, substantially as described.

29. The process of treating finely, divided material containingcarbonaceous components, which comprises transmitting heat body of hotgases to the upper surface of a mass of material capable of undergoing apropagative reaction, introducing a combustion-supporting gas at thelower surface of the mass, conducting the combustion-supporting gasupward through the interstices of the mass, controlling thermal andother conditions so as to pro agate the heat downward throughout ticbody of such mass by internal combustion. and withdrawing the volatileproducts of combustion at the upper surface, substantially as described.

30; The process of treating finely divided material containingcomblistion-supporting and other con'lponents, which con'n'n'isestransmitting heat from a moving body of hot gases to the upper surfaceof a mass of material capable of undergoing a prop reaction, introducinga gas re-. active with someof the components of the material at thelower surface of the mass, conducting the reactive gas upward throughthe interstices of the mass, controlling thermal and other conditions soas to propagate the heat .downward throughout the body of such mass byinternal combustion. and \vitl-ulrawin" the volatile products ofcombustion at tlie upper surface, substantially as described.

31. The process of treatingfinely divided material containing reactivecoi'nponents, which comprises transmitting heat from a moving body ofhot gases tothe upper surface of a mass of material capable ofundergoing a propagative reaction, introthtcing agas which is reactivewith some of the components of the material at the lower surface ofthemass, conducting the reactive gas upward through the interstices ofthe mass, controlling thermal and other conditions so as to propagatethe heat downward throughout the body of such mass by gases to they massby inan internal reaction, and Withdrawing the volatile products ofreaction at the upper surface, substantially as described.

32. The process of treating granular material capable of undergoinpropagative reaction, which comprises initiatlng a propagative reactionat one surface of a mass of material having definite bounding surfaces,said mass being of substantially uniform character throughout,transmitting a current of reaction-Snpporting gas through the masstoward'the surface of initial reaction, and controlling conditions so.as to cause the propagative reaction to travelinward through theinterstices in the body of the mass in a direction other than the flowof the reaction-supporting gas, substantially as described.

33. The process of treating material containing combustible components,which comprises producing ignition in a mass of material havingdefinite'bounding surfaces and capable of undergoing a propagativereaction, said mass'bclng of substantially uniform character throughout,feeding a gas current through the interstices in the mass. andcontrolling conditions so as to cause a backward propagation of theplane of ignition against the tiow of the gas current by means ofareaction internal to the mass, substantially as described.

34. The process of treating finely divided material capable ofundergoing agglomerative reaction, which comprises initiating anagglomerating reaction at one surface of a mass of the material, saidmass being of substantially uniform character throughout, transmitting acurrent of reaction-supporting gas through the mass toward the surfaceof initial reaction, and controlling conditions so as to cause theagglomerating reaction to travel'inward through the interstices in thebody of the mass in a direction other than the flow of thereaction-supporting gas, substantially as described.

35. The process 0 treating finely divided material containing heatdeveloping components and capable of undergoing agglomerative reaction,which comprises initiating an agglomerating reaction at one surface of amass of the material, said mass being of substantially uniform characterthroughout, intrmlucing a combustion-supporting gas at: another surfaceof the mass, conducting the combustion-supporting gas through theintersticesof the mass, and controlling conditions so as to propagatethe agglomerating reaction through the mass by internal comlalstion,substantially as described.

36. The process of treating finely divided material containingcombustible components and capable of undergoing agglomerative reaction,which comprises transmitting heat from a body of hot; gases to the.upper surface of a movable mass of the material, said continuouslyfeedin mass being of substantially uniform character throughout,introducing a combustionsupporting gas at the lower surface of themovable mass, conductin the combustionsupportin gas upward t rough theinterstices of t 1e movable mass, and controlling thermal and otherconditions so as to propagate an agglomerating reaction downward throughthe movable mass by internal combustion, substantially as described.

.37. The

- combustion, substantially as described.

38. The process of continuously treating i recess ofcontinuouslytreating finely dlvi ed material containing combusfinely divided ironoxid, which comprises mixin with the iron oxid the minimum uantity offinely divided fuel required to orm a mixture capable of undergoingagglomerative reaction; continuously feeding the mixture to the movingperforated hearth of a reverberatory furnace to form a moving mass;continuously transmitting heat from a body of hot gases to the uppersurface of the moving mass; and continuously condu'ct- 40 ing acombustion-supporting gas upward through themoving mass; the conditionsrelating to the composition of the iron oxid mixture, the compositionand. tem11)erature of the hot gases, and the composition, temperatureand pressure of the combustionsupporting gas being so correlated as tocontinuously initiate an agglomerating reaction at the upper surface ofthe moving mass, and so as to continuously ropagate the agglomeratingreaction ownward through the moving mass.

In testimony whereof I have hereunto set my hand this eighth day ofJune, 1909, in the presence of two witnesses.

a mgmuuolt W. Yos'r.

Witncsses:

RALPH MUMILLAN, EDWARD A. BERN.

